Look! Dave on the phone.A. talksB. are talkingC. talkD. is talking

问题补充：

Look! Dave on the phone.

A. talks

B. are talking

C. talk

D. is talking

答案：

A. talks

B. are talking

C. talk

(答案→)D. is talking

解析：考查现在进行时。look！是现在进行时的标志词。句意：看，大卫正在通过电话交谈。Dave为单数第三人称做主语，谓语动词应用单数，所以选D。